I propose to continue our studies on the protoplasmic streaming in live cells by the technique of laser Doppler spectroscopy. Our recent successes in the study of the streaming in Nitella flexilis will be pursued by furter experiments and more sophisticated analysis of the velocity profiles which we have measured. Extensions of this work to the study of the protoplasmic streaming in other organisms, particularly Physarum polycephalum and Chaos chaos, will be continued. Careful and precise monitoring of the electrical potentials in these organisms will be conducted to correlate the electrical potential with the flow velocities, velocity distributions, and reversal periods. The local effects of inhibiting drugs such as cytochalasin B will be investigated. Further experiments on the local inhibition of streaming by laser light of various wavelengths will also be conducted.